Furnace protection



Nov. 11, 1924.

L. W. GERHARDT FURNACE PROTECTION Filed Aug. 14, 1922 I/lr menig/1 fefaf'a.

calls' Patented Nov. 11,1924.

Laim?" remmen Pao'rncfrron.

` applicati@ nieu August y14, 1,922. seri'aung'sslgesq. ff i To a-ZZ whom t may concern.' i

Be it known'that I,LoUrs W. GERHARDT,

a citizen ofl the United States, `residing at Coatesville, inthe county of*r Chester and State of Pennsylvania,have.inventedv certain new .and useful Improvements in Furh4 erence to melting furnaces 'of 'the openy hearth type, or heating furnacesconstructi-` ed largely of refractory materials. j

In operating furnaces of this character, and particularly those of the reversing vtype whichare regenerative or recuperative, it is' found that the heat of the outgoing gases is so great as to melt, fuse, flux'or 'otherwise destroy the end walls or portions" thereof, and thisalso causes irregularities *in the shape of the fines andl channels, whichleads to incorrect introduction and mixtures of the gases, 'besides which 'the "frequent destruction of thesefwalls necessitates temporary shut-downs for repairs while the parts so destroyed are being replaced or rebuilt. This destruction ofthe end walls of a' furnace generally occurs at places opposite the ports yor passages where the outgoing products of combustion impinge against the walls and are thereby deflected' downwardly to the regenerators,frecuperators, or stack iues. These portions as sometimes built are composed of a wall of silica brickk about thirteen and one-half inches thick, buton account of the action of the intense heat off the outgoing products of combustion, these bricks or some of them are being continu-` smaller frame refractory materials are set Vwhichmay be easily removed to' permlt ac` ally luxed or destroyed, so that such por# tions ordinarily last only aweek or ten days, and at the end of this time neww'alls or portions are'usually necessary, and in making such repairs, under' the diihcult conditions of heat, the cost of labor is excessive and the workl cannot be doneverywell, 'which again leads to quick destruction ofther walls when again'put in use, for thel reasons above stated. In addition tothis such repairsde# lay the operation of the furnace and increase thecost of production. y y

Instead kof this prior usual construction I provide a hollow-frame, which may be: cooled by water orother'fiuids arranged-to circulate therethrough, land `@within"'a'nd around this frame I construct wallslof-ref fractory materials, preferably-of diere'nt characters, each-'best adaptedfvtosuit ther heat and conditions to which it is subjected.

-My coolerfis made in the' shape of a frame somewhat vsimilar tol a doorr orfwindow frame, but with'a pair-kof -side members', a bottom member, atop member andfin-terme# diate members, vall'of'which-Jarehollow and through which c'oolingfiiuidcirculates, andl Loursw.' enanaan'r, or' coAfrsvILnn, 12min'saurait'1:15341.fly

my coolingf'frame is 'made in this shape in order; that it may be* adequate for 'the pur-f pose and not of undue size, andby re'asonofy the frame' construction it; proyidesf` ample cooling, :whereas if such a strficture were made in the shape of a boX, too'much'vcooling effect would be produced 4and in addition t'of which certain parts'would be burned outior",` destroyed owing ltothe lack yof circulation* of cooling iiuid,=a`ll of which is'obvi'at'ed by mycon'struction;1A f

My frameis provided withabutting'Land `usual side jambs, base and lintel portions,"` and this frame ymay also 'be provided with.

onev 'orA `more cross ymembers `connecting the Jambs in order to strengthen thefframe and" at the same time assist in` coolingthefadf' Jacent parts of the refractorymaterials. I y may also provide within the `framea 'smaller adjacent refractory material'- composed of-v f brick walls 'of suitable kinds, someofvwhichjV ser frame which forms -`a portion thereof, fandif which is also water-cooled, `and within this" cess to the portfor iue whichfthey are oppofl repair. This arran ement therefore allows' forquick and rapi inspection and're'pair of the port'by removing the smaller portion i of the .refractory materialawithin the-small* opening in'l the frame, soIthatf-the're isprac# tically nace occasioned `by this.

The water 'or other cooling'y fluid' referi A ablyenters thehollow' fra-me at' the ottom and circulates upwardly throughout the vadepth as the length of the brick. The up.

per cross arm is provided with a small rectangular hollow frame, preferably formed integral and connecting with the other po-rtions of the frame, lhaving an opening of approximately one square foot or so in size, which-willexactly contain a number of standard first-,class hard flint clay bricks, which-can be removed as necessary without disturbing the other parts of the wall.

yeo y 4the other vmore magnesite brick.

Thesebrick may thus lhe frequently removedA for examination and repair of the ports and fines adjacent ythis opening, and the use yof these clay bricks reducegthe ,cost of ,construction and saves loss and damage of permanent but expensive -My frame is preferably rconstructed of` a steel plate, which may be one-half inch orthereabouts in thickness and is made hollow by flanging three of the sides, while the fourth side, after being cut to shape., is welded in place with its edges contiguous to the other edges of the frame. In the kbottom cross arm or base I preferablyv weld two pipe sleeves, to onek of which the inlet pipeis `connected,. while-the other is provided with a valve forziiushing or draining thesame; I

In the upperipart of the frame, as illus-` trated, is an auxiliary frame within lthe main frame, in which is welded a pipe nipple, to which is securedan outlet pipe, andanother nipple is welded in the top member,

both connected together and to an outlet pipe, and the water or other 'fluid discharged throughthem may be used forcoolingl other portions ofthe furnace coolers, or discharged as'desired.

Inorder toeasily handle the frame I; provide ktwo lugs welded to the top portion thereof, whichfare provided with holesl in-v y1n the wall ofthe furnace; Figure 3 is a which ,liftingjhooks,etc., may be inserted.y

My frame may be placed in position when thefurnace is first constructed, or `when the furnace has been shut down for repairs, and the inner portion of the frame should `be preferably seated flush with the inner surface of the gas uptakewall, and in order to allow forexpansion a space should be left between the frame kand .ther adjacent brickwork, and .this space will be closed as the brickwork is expanded by the heat.

VAAfter the furnace is brought up to `heat the .joint may also be pointed up, if desired` so as to vbe thoroughly sealed asnecessary.

,elevation through the- After the frame is in place the three main panels are preferably ylined withmagnesite brick and on the outside of the frame a wall of nine-inch silica brick is laid the entire width and height of the frame. The silica brick panel is bonded to the magnesite lining on the bottom course of the middle magnesite panel, thus helping to hold the frame and walls in position.

I also prefer to provide expansion joints of about a half inch on one side and the top of both the lower and middle panels, and a somewhat similar expansion joint around the upper panel of the brickwork.

I prefer to provide an opening in the outer Wall of silica brick to correspond with the small opening of the frame in order toallow ready access to the clay brick which are set within theopening. As these `clay brick dov not expand very much they are easily removed and replaced.

I preferito form the upper portion of the frame arched orsegmental, and above the same I construct a brick relief arch to support the end wall of the'furnace over the frame, Which. arch 'preferably extends only to the face of the lifting straps, the outer silica brick panel extending above this point upto the port arch so as to permit1 the removal ,of the frame vwithout damage to the relief arch'.r

4As compared with prior constructions, I find by actual practice that the portion of the furnaceconstruction in the neighborhood ofcmy bulk-head frame will last six or eight times as long as without it, with consequent economy and ease of operation.

Having thus given ageneral description of my invention, I will now, in order to make the matter more clear, refer to the annexed sheet of drawings, which forms part of this specification, and in which like characters refer to like parts z- Figure l is a vertical longitudinal sectional4 elevation through a portion of the end of an open hearth furnace, illustrating the application of myvinvention, the section bein'gtaken on the line I-I of Figure 2; Figure2 is anend elevation of the top portion of an open hearth furnace illustrating the position of my improved water-cooled frame on the line IV-IVV of Figure 3; Figure rv5 is an elevation of my improved Water-cooled frame, and Figure 6 vis a vertical sectional frame taken ony the line VI-VI of Figure Referring now to the characters of reference on the drawings z-l represents the furnace hearth in generalgQ is the end wall of the lfurnace .composed of bricks ork refractory of av furnace, andi the. other end .may be of similar construction, v `8 is .the .outer portion of the walladjacentto` my water-cooled frame, whichwall is preferably composed of silica brick; 9 is the water-cooled framek as a who'le,jwhich is hollow, asvbefore stated, 10 being the side'portions thereof, and 11 the horizontal portions uniting the same; 12 is the auxiliary frame connected with the upper horizontal member, and 13 is the upper curved or arched portion of the frame. Around the outer portion of the frame are spaces or expansion joints 14, while 15 are the outlet pipes which are connected to the joint outlet pipe 16. Theinlet pipe is one of the two pipes 17 at the bottom, one of Whichpmay be connected to the supply of cooling Huid and the other may be provided with a valve for draining or iushing the frame. The lifting lugs 18 are welded to the upper portion of the frame and are pro-` vided with holes 19 therein in which lifting hooks or other tools may be inserted.r 20 is the magnesite brick wall within ythe panels of the'frame, while the small opening for access to the gas port'is 21, within which is constructed the smaller wall of clay brick 22.

Although I have shown and described my invention in considerable detail, I` do notk Wish to be limited to the exact and 'specific details thereof as shown and described, but may use such modifications in, substitutions for, or equivalents thereof as are embraced within the scope of my invention, or as pointed out in the claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is l. The combination with a furnace, of a Wall, subject. to destructive heat, of a fluidcooled frame, having a plurality of openings, mounted therein, -comprising separate but connected-hollow side, top and bottom portions, with refractory materials surrounding and Within the same.

2. The combination with a furnace, having an endwall subjectl to destructive heat. of a hollow fluid-cooled frame mounted therein, comprising substantially straight side and bottom portions and an arched upper portion, 'refractory materials abutting theouter side of same with a relieving arch above said upper portion and refractory material within said frame.

2%. The combination with a furnace end wall, of a hollow duid-cooled frame, having a pluralityv of openings, mounted therein provided with separate but connected` side,

bottomand top-portions "and intermediate hollowy portions connecting said side portions. f

4. The combinationgi'witlr Vfurnace'l'end` wall, lof a hollow fluid-cooled frame,having` a plurality of' openings, `mounted, therein provided with separate but yconnected side, bottom and top port-ions, and intermediate hollow port-ions connecting said side por-l tions, and .refractory material "surrounding and Within said frame.

The combination; with a furnace end Wall, of a hollow fluid-cooled frame, having a pluralityof openings, mounted therein, comprising separate but connected top, side and bottom portions, and intermediate portions connected to said side portions, and` another portion connected with one of said intermediate portions, enclosing an open.

ing, bricks removably mounted in said opening and Within and around the other portions of said frame.

6. The combination with the end wall of `an open hearth furnace, of a fluid-cooled frame, having a plurality of openings, set Within the same at and near the location where outgoing gasesA contact., comprising within and around said frameV and within said repair openingand means for supplyseparate but connected side portions, a loot-y tom portion, an upper arched portion and an intermediate portion surrounding a repair opening. refractory materials mounted within and around said frame and Within said repair opening, means for supplying cooling fluid to and delivery of the same from said frame, and a valve-controlled drain opening in the lower portion of said frame,v

8. A water-cooled frame. of the character described` comprising side members. a bottom member, an upper member of arch form. one or more intermediate members connecting said side members. one of said intermediate members being provided with members forminga smaller auxiliary opening Within said frame. said frame being formed of pressed metal plate integrally welded together. and provided with inlet and outlet opcnings for the circulation of iuid therein. i

9. A Water-'cooled frame of the character described. comprising side members. a` bottom member. an upper member of arch form` one ormore intermediate members connect- .ing said side members, one of said intermediate members being provided with members formingga Smaller auxiliary opening within said frame, said frame being formed of pressed metal plate Welded together, and providedwith inlet and outlet openings for the circulation of fluid therein, magnesi'te brick Within the main panels ot' said frame; and clay brick Witliiirtlie auxiliary opening thereof. I

10. A Water-cooled frame of` the character'y described,` comprising side members, a `bottom member, ail-upper member ofy arch` form, one 0r more intermediate members connecting said side members, one of said intermediate members being provided with members forming ingfwithin said frame," said/frame being formed of pressed metalwplate Welded together, :1n-d provided with inlet` and outletl openings for the circulation of' fluid therein',

magnesite brick' Within the main panels 'of' said frame, clay briekwwithin they auxiliary opening thereof, and an outer Wall ot' silica brick adjacent said frame,

In'witness whereof Iyhereunto 'affix my signature. i, f i

LOUIS GERHRDT.4

a Smalle-rv lauxiliary open-v 

